diy gas refilling

[Dr Bob]

2 minutes ago, Mike the Boilerman said:

 

I too have heard about certain LPG products rumoured to be propane and butane mixed (automotive LPG, and 'patio' gas). Is this technically not possible then Dr Bobski? Or inadvisable and improbable?

Yes, no problem mixing them, but the resultant mix will have a boiling temp in between and the pressure in the cylinder will be inversely proportionate (is that the right way round.........bombay sapphire effect) to the boiling point. Don't put a low boiling mixture into a butane tank. 

Not a clue what mixes these are but red tanks hold higher pressure and blue ones don't.

[rasputin]

bombay sapphire sounds like a great curry

[Dr Bob]

5 minutes ago, TheBiscuits said:

I think he was warning about putting the gas in the wrong bottle.  Mixed propane/butane is very common - you will probably have some for your soldering torch.

Yes, well done. You're not crackers.

[MtB]

Just now, Dr Bob said:

Not a clue what mixes these are but red tanks hold higher pressure and blue ones don't.

 

ISTR the pressures in both butane and propane bottles are surprisingly low. In the order of 2 bar (ish) we were taught. 

 

Might have to have a goggle and see if this is right!

[Alan de Enfield]

 

Propane (LPG, Liquefied Propane Gas) This is a great hot burning fuel that works at low temperatures and at high altitudes.  Due to high pressures of propane (close to five times that of butane at room temperature), propane canisters are often made from of thick heavy gauge steel.  Pure propane is not recommended for stoves designed to run mostly butane and/or isobutane without a pressure regulator or careful user control.   Propane is generally used for heavy duty stoves, lanterns, heaters and torches.  It can be much easier to find and more affordable than other gas fuels for stoves.  Propane is often available at hardware and grocery stores.   Boiling point: -43° F (-40°C).  Fuel will not vaporize well below its boiling point.

 

 

Butane (n-butane) Works well at high altitudes but burns poorly below 40° F due to poor vaporization at low temperatures.  Butane is commonly used in backpacking and portable stoves, lighters, small torches and as a propellant for aerosol cans.   Boiling point: 31° F (-0.5°C).  Fuel will not vaporize well below its boiling point.

 

 

Isobutane Isobutane is a structural isomer of butane with a lower boiling point.  Manufactures claim that isobutane provides a steady flow without tapering off as the canister empties and is added to butane to increase its performance.  Because of the greater vapor pressures of isobutane compared to butane, you may experience much greater gas flow.  This increased pressure can cause a stove to blow itself out if it is turned up too high or possibly even damage a stove not designed for isobutane.   Boiling point: 11° F (-12°C).  Fuel will not vaporize well below its boiling point.

 

 

Propene (aka propylene, methylethylene and MAPP Gas) This is used for medium to heavy soldering and brazing and not intended for stove use.  It has an extremely low boiling point, which makes it useable after gas fuels used for camping fail to work in the bitter cold.   Boiling point: -54° F (− 47.6°C).  Fuel will not vaporize well below its boiling point.

 

[MtB]

 

(And curiously I've bin on the Bombay Sapphire too tonight!)

[Dr Bob]

1 minute ago, Mike the Boilerman said:

 

(And curiously I've bin on the Bombay Sapphire too tonight!)

...with a nice bit of lime thrown in

[MtB]

5 minutes ago, Dr Bob said:

...with a nice bit of lime thrown in

 

I'm not sure putting lime Ca(OH)₂ in your gin is going to be very good for you....

 

 

 

 

[Dr Bob]

2 minutes ago, Mike the Boilerman said:

 

I'm not sure putting lime Ca(OH)₂ in your gin is going to be very good for you....

 

 

 

 

I wish I knew how to do subscripts.

[MtB]

9 minutes ago, Dr Bob said:

I wish I knew how to do subscripts.

html is your _FRIEND....

 

_text ... but use square brackets [ ] instead of < >

 

 

Edited September 7, 2018 by Mike the Boilerman
Edit to get the stoopid html [sub]RIGHT[/sub]!!

[Alan de Enfield]

 

 

Edited September 7, 2018 by Alan de Enfield

[bizzard]

The Chris Bonington expedition used a mixture of butane and propane in their portable camping stoves when climbing Everest in 1975, even so above a certain height they had to resort back to paraffin pressure stoves.    I've often bought propane gas  bottles painted red over the blue paint of a butane bottle, you can see the blue paint where red paint has scraped off. I think I have a bottle like it in my locker at the moment.

[Alan de Enfield]

7 minutes ago, bizzard said:

The Chris Bonington expedition used a mixture of butane and propane in their portable camping stoves when climbing Everest in 1975, even so above a certain height they had to resort back to paraffin pressure stoves.    I've often bought propane gas  bottles painted red over the blue paint of a butane bottle, you can see the blue paint where red paint has scraped off. I think I have a bottle like it in my locker at the moment.

Interesting - how do you get around the fact that the Butane & Propane connectors are different ?

[rasputin]

not at the bottle?

 

[bizzard]

10 minutes ago, Alan de Enfield said:

Interesting - how do you get around the fact that the Butane & Propane connectors are different ?

They always have the screw type propane fitting. They must swap it for the clip on butane type.

[Jen-in-Wellies]

11 hours ago, Mike the Boilerman said:

html is your _FRIEND....

 

_text ... but use square brackets [ ] instead of < >

 

 

<Pedant> Actually something called BB code, rather than html. Similar to many html commands, but a subset used for formatting text and available on many web forums like CWDF. Good for _subscripts, ^superscript and lots of other possibilities not available from the usual editing menu.</pedant>.

https://en.m.wikipedia.org/wiki/BBCode

 

Jen

 

Edited September 8, 2018 by Jen-in-Wellies

[MtB]

9 minutes ago, Jen-in-Wellies said:

<Pedant> Actually something called BB code, rather than html. Similar to many html commands, but a subset used for formatting text and available on many web forums like CWDF. Good for _subscripts, ^superscript and lots of other possibilities not available from the usual editing menu.</pedant>.

https://en.m.wikipedia.org/wiki/BBCode

 

Jen

 

 

Good point. A trick that often works on BBs with a profanity filter is to format then unformat your profanity part way through the word. This defeats some profanity filters. 

 

Eg typing for example “fu<i><\i>cking” often slips the word past the profanity filter  brilliantly, much to the amazement and admiration of your B.B. peers! 

Edited September 8, 2018 by Mike the Boilerman

[TheBiscuits]

1 hour ago, Mike the Boilerman said:

<\i>

</i> 

[Guest]

14 hours ago, rasputin said:

I have a cooker that runs off bottle pressure gas, (I think) and there are all sorts of crazy systems on caravans that carry the gas at bottle pressure through a pipe to a remote regulator.

 

the price of gas in camping gas bottles seems to have gone though the roof, so much , that I have to do something, maybe find a way to install a calor bottle.

Not sure what you mean here, but gas bottles in caravans normally use a simple pigtail pipe to connect to a regulator mounted on the back wall of the gas locker. It then flows to the applianceces through simple pipework via. a manifold where you can isolate the various appliances. I'm not sure why you would describe that as 'crazy'.???

13 hours ago, bizzard said:

The Chris Bonington expedition used a mixture of butane and propane in their portable camping stoves when climbing Everest in 1975, even so above a certain height they had to resort back to paraffin pressure stoves.    I've often bought propane gas  bottles painted red over the blue paint of a butane bottle, you can see the blue paint where red paint has scraped off. I think I have a bottle like it in my locker at the moment.

Same here.

 

[Dr Bob]

13 hours ago, Mike the Boilerman said:

html is your _FRIEND....

 

_text ... but use square brackets [ ] instead of < >

 

 

 

2 hours ago, Jen-in-Wellies said:

<Pedant> Actually something called BB code, rather than html. Similar to many html commands, but a subset used for formatting text and available on many web forums like CWDF. Good for _subscripts, ^superscript and lots of other possibilities not available from the usual editing menu.</pedant>.

https://en.m.wikipedia.org/wiki/BBCode

 

Jen

 

Cor....you lot are very clever!

[Guest]

14 hours ago, Dr Bob said:

I wish I knew how to do subscripts.

There used to be the option to format your text so, direct from the reply box tool bar, but that seems to have vanished at some point.

 

[Machpoint005]

16 hours ago, Alan de Enfield said:

AND listing the risks involved, and how to minimise them.

The only same way to minimise these risks -- ie reduce risk to the minimum -- is not to do it.   

[Alan de Enfield]

2 minutes ago, Machpoint005 said:

The only same way to minimise these risks -- ie reduce risk to the minimum -- is not to do it.   

Lets not go boating, driving, hiking, eating or breathing - then there is no risk but we have no 'life'.

 

The world would be a very different place if man had not pushed the boundaries of what is safe to do.

I expect the Wright brothers sat at Kittihawke and thought - "Nah, lets not bovver, it looks a bit dangerous"

[Momac]

21 hours ago, Alan de Enfield said:

Most modern camping gas is a '80/20 or 70/30 mix to allow cold weather usage.

 

https://www.gooutdoors.co.uk/coleman-performance-gas-c300-p366834

 

A (70/30) butane/propane gas mixture in a threaded self-sealing cartridge, compatible with all Coleman resealable appliances.

While Campingaz as  supplied  in a 907 cylinder is 100% Butane.

[Alan de Enfield]

1 minute ago, MartynG said:

While Campingaz as  supplied  in a 907 cylinder is 100% Butane.

Yes - just as you can still buy bigger cylinders from Calor in 'pure' Butane or Propane.

 

Not many people camping / hiking up the Pennine Way, Snowdon or the Cairngorms or other 'cold' regions would consider carrying a 907 Cylinder.

With my 230g 70/30 mix cartridge I can boil enough water for 12 meals and 12 mugs of tea.

 

A 907 cylinder weighs 6.4kgs

My total 3-day pack (including tent, sleeping bag, mattress, food, clothes, water, stove, gas, etc etc) only weighs 10kg.

 

I certainly wouldn't be taking a butane gas cartridge in the 'hills'. It was bad enough in the Scouts when we only had the Campingaz Bleuet S200 butane cartridge and had to sleep with them in our sleeping bags - at least they are now a Propane / Butane mix (it is just the 'big' cylinders that are not 'mixed').